My 2014 Passat TDI experience so far

Does the liquid smell urine-like ? It would be very unfortunate if the cabin stunk after an exchange.

 

Diesel exhaust fluid ("AdBlue") has no detectable odor.

JH is correct however, the urea in the aqueous solution does produce a white crystalline substance if spilled.

 

Mercedes apparently is already using filters (GPF) on at least one of its (European?) models - Green Car Congress: Report: Mercedes-Benz equipping S500 with gasoline particulate filter .

 

If spills aren't cleaned up, the DEF can damage the car's paint. How close are painted surfaces to the DEF filler? I believe the Cruze diesel's filler is also in the trunk. Not convenient, but it isn't something that needs to added everytime you stop for fuel.

DEF is just water and urea. While there is less urea in urine, it also contains other metabilites, salts, and hormones. Then bacteria will start feeding on it fairly quickly.

 

Prius tail pipe, as any petrol engine, has no excess air.
Diesel flows a lot of air through (more velocity, and PM more diluted), and probably the PM do not aggregate as much over the inner surface because of the temperatures during the regen cycle.

 

Then it is likely a cost cutting measure to use the same sheet metal as the gasoline version.

Or there is simply a lot less PM getting past the DPF to begin with.
Pre-DPF diesel tailpipes are just as, if not more, dirty as gasoline ones. Same engine displacement means about the same amount of gases flowing through the exhaust, and many diesels have larger bore exhaust than gasoline.
PM is produced by both types of engines. A filtered diesel emits less particulates than a direct or ported injection engine. So there is simply less to accumulate inside the tailpipe.

 

At the end of the day the inside of a modern diesel passes the dirty finger test.

 

I will not try to explain the simple fact there is a lot more excess air in a Diesel cycle engine.

 

If you mean unburnt oxygen, you don't need to explain it; they burn lean most of the time.
Or if you are referring to the lack of a throttle plate, which creates a partial vacuum in a petrol? Since the majority of exhaust flow is from combustion heat, the extra air that a diesel inhales isn't going to help 'sweep' the tailpipe clean. It will speed up due to heating from the explosion, but the fuel is expanding and speeding up to a far greater magnitude in the explosion. If it were the case, then pre-DPF diesel tailpipes would be clean also. They aren't, and depending on how often they get washed, the their bumper and backside can also have a build up of soot. Which can also be said of poorly tuned and modified gas cars.

The DPF is right after the engine, and can even be part of the exhaust manifold. The extra heat and gas expansion from regeneration has to pass through the rest of the exhaust system. That, and the frequency of the cycle likely mean the exhaust speed and heat shouldn't be much different than a non-DPF diesel. Besides, if it has a DPF, there simply isn't any particulates to accumulate.

ICEs produce particulates. The amount depends on the fuel(diesel>gasoline>CNG), and engine design(DI>port), but there will be enough to dirty up the tailpipe insides. Unless there is an exhaust filter in place. Regulations are written so that diesels have to reduce their particulates to virtually zero, and a clean tailpipe is a very minor benefit of that.

 

The consensus of opinion on this website is that diesels are all dirty, smelly, sooty and blow smoke. It has been suggested that this only applies to older diesels but Americans generally seem to only recall diesels from 1979 when they last saw them in number.

I have previously mentioned about the inside of tail pipes being totally clean after tens of thousands of miles and how the previous opinion of diesels being sooty is out of date. I could never find a photo to back this up, until a kind member took a picture of his.

Modern diesels are many things, but smokey and sooty they are not.

 

I went out to inspect my Leaf pipes but gave up after not being able to find it...

 

The days of black/blue smoke belching out of the tail-pipes of modern diesels is almost gone! We have very strict emissions tests here in Ireland (cars must be tested every 2 years up to 10 yrs old and every year thereafter) and all the modern diesel cars are passing these tests. The only time that they may struggle with the test of if there's very big mileage on the car, but if they're looked after service-wise, there's no issues.

If I had a long motorway commute, I'd be driving a modern diesel car, but as I live in Dublin city & 75% of my driving is city driving, I'll be sticking with the Prius or similar car

 

What about the smokestack of the coal plant that is powering your Leaf?

 

I was waiting for someone to say that! lol

He probably has a solar farm there to power the Leaf

 

His signature states he has a 10kw solar array. I imagine that would significantly help reduce soot.